Here,\(Y_{N2}^{eq}(0)\)  is the initial equilibrium number density [1]} of \(N_2\)  and is given as \(Y_{N2}^{eq}(0)=135\zeta (3)/4\pi ^4g*\)  with
\(g*\sim 106\)  being the total relativistic degrees of freedom at \(T\sim M_{N_2}\) .
As shown in the next section, the washout efficiency parameters\((\eta )\)  in both sectors
turn out to be \(\mathcal {O}(1)\)  and imported in Eq.(REF ).
